Data from: Whistling shares a common tongue with speech: bioacoustics from real-time MRI of the human vocal tract

Most human communication is carried by modulations of the voice. However,
a wide range of cultures has developed alternate forms of communication
that make use of a whistled sound source. For example, whistling is used
as a highly salient signal for capturing attention, can have iconic
cultural meanings such as the cat-call, enact a formal code as in
boatswain’s calls, or stand as a proxy for speech in whistled languages.
We used real-time magnetic resonance imaging to examine the muscular
control of whistling to describe a strong association between the shape of
the tongue and the whistled frequency. This bioacoustic profile parallels
the use of the tongue in vowel production. This is consistent with the
role of whistled languages as proxies for spoken languages, in which one
of the acoustical features of speech sounds are substituted with a
frequency modulated whistle. Furthermore, previous evidence that non-human
apes may be capable of learning to whistle from humans suggests that these
animals may have similar sensorimotor abilities to those that are used to
support speech in humans.